1. Field of the Invention
The present invention relates to:                a method for manufacturing a wooden beam constituted of basic elements defining its ridges and forming at least four elongated members connected by other basic elements forming at least two crosspieces, the elongated members and the crosspieces being assembled in assembly zones by the gluing of their contact zones,        a wooden beam manufactured according to the aforementioned method, and        a wooden frame for the construction of a building.        
2. Discussion of Background Information
As known in the field of construction, and more particularly in that of wooden frame constructions, the wooden beams are unitary and carved from the block, or are made of wood core plywood, or constituted by the assembly of smaller basic elements. The unitary wooden or wood core plywood beams are heavy, cumbersome, difficult to handle, rigid, have a high ecological and economical cost, and tend to become fissured.
Wooden beams that are constituted of the assembly of smaller basic elements allow the lightening of the frames, the ease of assembly and the lowering of construction costs. The assembly of the basic elements together is obtained in a known and non-limiting manner by clamps, glued dowels, pins, screws or complementary glued nesting forms. The French Patent FR-A-2 572 759 describes a beam obtained by the assembly of four parallel square rulers connected together by crosspieces that are arranged at an angle in a herringbone pattern. The assembly is achieved by nesting and gluing complementary machined grooves in the square rulers and crosspieces, respectively. The object sought by this invention is to obtain rigid beams having a substantial length. It is also with this object that the square rulers are pre-stressed before their assembly and gluing, or that the square ruler lattice is doubled. The British Patent GB-A-1 603 357 describes a beam having the same construction but in which the crosspieces and square rulers are assembled by gluing plywood spacers inserted therebetween and allowing the stiffening of the assembly.
A major drawback to this type of assembly is that these various attachment systems create rigid connections between the basic component elements of the wooden beam, and do not allow any freedom of movement between these basic elements. The beam obtained no longer has any elasticity. Consequently, when it is subject to forces, these rigid connections create very substantial stresses in the assembly zones that weaken the basic elements involved, which can cause them to crack or even break. As a result, this technique does not allow the manufacture of wooden beams having a substantial span. Indeed, the bending due to the load applied on these wooden beams creates forces that are too substantial in the assembly zones, and leads to the breaking of the wooden beams. The manufacture of these types of wooden beams having a substantial span therefore necessarily requires the use of at least one intermediary bearing wall that makes it possible to reduce the stresses sustained by these wooden beams.